ePrints

Populus nigra L. establishment and fluvial landform construction: biogeomorphic dynamics within a channelized river

Lookup NU author(s): Dr Borbala Hortobagyi

Downloads

Full text for this publication is not currently held within this repository. Alternative links are provided below where available.

Abstract

Populations of the riparian pioneer species Populus nigra L. which establish on alluvial bars within river channels modulate sediment dynamics and fluvial landforms. Dense cohorts of P. nigra have colonized gravel point bars along the channelized River Garonne, France, during the last 20 years and have enhanced the vertical, lateral and longitudinal development of the bars. For this period, the geomorphic characteristics of two wooded point bars on this laterally stable river are closely linked to the spatial distribution and intensity of establishment and resistance of different cohorts of P. nigra. Furthermore, P. nigra colonization dynamics were controlled by engineer effects of this same species. This relationship is illustrated by a significant correlation between key geomorphic and biological variables measured in situ and characterized with a set of four aerial photographs taken between 2000 and 2010. The development of wooded point bars, which are discrete biogeomorphic units, over the studied period, appear to result from a specific biogeomorphic positive feedback of matter aggregation and vegetation establishment related to sediment trapping and stabilization by pioneer engineer plants. We propose a conceptual model of biogeomorphic unit construction for channelized, lateral stable rivers. We consider the resultant biogeomorphic units as functional from an ecological point of view because P. nigra enhances at the cohort scale (i) its own inherent capacity to resist hydrogeomorphic disturbances, and (ii) its resilience capacity as a result of successful colonization, especially downstream of mature poplar stands.

Publication metadata

Author(s): Corenblit D, Steiger J, Charrier G, Darrozes J, Garófano-Gómez V, Garreau A, González E, Gurnell AM, Hortobágyi B, Julien F, Lambs L, Larrue S, Otto T, Roussel E, Vautier F, Voldoire O

Publication type: Article

Publication status: Published

Journal: Earth Surface Processes and Landforms

Year: 2016

Volume: 41

Issue: 9

Pages: 1276-1292

Print publication date: 03/07/2016

Online publication date: 08/04/2016

Acceptance date: 06/04/2016

ISSN (print): 0197-9337

ISSN (electronic): 1096-9837

Publisher: John Wiley & Sons, Inc.

URL: https://doi.org/10.1002/esp.3954

DOI: 10.1002/esp.3954

Altmetrics

Share